Wirecast is not available for Linux but there are some alternatives that runs on Linux with similar functionality. The best Linux alternative is OBS Studio, which is both free and Open Source. If that doesn't suit you, our users have ranked more than 25 alternatives to Wirecast and five of them are available for Linux so hopefully you can find a suitable replacement. Other interesting Linux alternatives to Wirecast are VokoscreenNG (Free, Open Source), Snowmix (Free, Open Source), DVSwitch (Free, Open Source) and ffscreencast (Free, Open Source).
DVswitch is a digital video mixer intended for interactive live mixing of several incoming DV video streams. It was originally designed for the needs of DebConf; It has now been used for various other conferences, meetings and live musical performances.